Anatomy and Physiology focuses on the immune, respiratory, and digestive system for the 2023 season. Scioly.org is the recommended source for this because it contains all of the information needed, but some extra sources are below.
You are allowed one 8.5 x 11 in sheet for this event. It may be laminated/covered by a sheet protector. More details are in the rules, but you can buy some sheet protectors below. You are also allowed two standalone non-programming, non-graphing calculators, which you can also buy from the links below.